Archives: Traffic Flow

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: zippers for roads? You betcha.

All traffic isn't created equal.

Zippy Traffic...via Zipper

For example, you've likely noticed that the morning rush hour often has greater traffic coming into the city from the suburbs and that the evening rush hour traffic clogs up the outbound lanes.

So, we tend to have traffic moving much more slowly in one direction than the other.

Accidents and our tendency to rubberneck them also cause the traffic to bunch in one direction. (Yes, we can keep listing these reasons for a while.) Unfortunately, building new lanes for our roadways can be prohibitively expensive, and it often isn't even possible, especially where bridges are concerned.

There is a fascinating solution, though:

Road zippers are heavy vehicles that have the ability to move concrete lane dividers across a lane, widening the road for one direction of traffic, narrowing it for the other. This requires a special type of moveable barrier, with shorter segments linked together by flexible steel connectors.

The road zipper, plus new barriers, are far, far cheaper than an entirely new lane. They actually pick up the segment lines using a little conveyor system, essentially acting on the same principles as a screw or a ramp (though Jeff Mann, The Yard Ramp Guy, might think I'm stretching that definition a bit).

Road zippers can move the lane at up to a top speed of 10 mph, depending on traffic, and is much safer than trying to manage traffic with cones and lights. They're especially useful on bridges. Crews on the Golden Gate Bridge have been employing a road zipper since 2010 to manage rush hour traffic, to great effect.

Any road crew that's worked on a bridge isn't going to have particularly fond memories of dealing with bridge traffic, and the road zipper provides an effective solution. We can also use this method to speed up bridge re-decking projects, moving the barrier to protect the work zone.

Transportation authorities utilize road zippers all around the world, and they're especially popular in the United States and Australia. Many cities use them on a permanent basis, while others lease them temporarily during construction work.

Even if they weren't so useful logistically, I'd still like them: they're just plain cool.



“If you don’t know where you are going, any road will get you there.”

— Lewis Carroll

Yard Ramp Guy Blog: Ramps for Material Handling

This week, my friend The Yard Ramp Guy shows us how yard ramps and strawberry Pop-Tarts are connected.

Click HERE to read about my new favorite connection.

Archives: Evolution of the Screw

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original contributions. And so, my From the Archives series. This week: Turn, turn turn: the evolution of the screw.

Screws are a magnificent invention. I've talked about them plenty – think of them simply as ramps wrapped around an axle – so why wouldn't I be interested? They’re simple machines and they literally help batten down the hatches. I figure it’s time to unscrew the lid on their history.

Our old friend Archimedes probably invented the screw. Archimedes' screw is used to pump water uphill, usually for irrigation, through a tube with a metal screw inside: as you turn the screw, the threads scoop up water and push it to the top.

Archimedes' screw

Archimedes' screw

Interestingly enough, we still commonly use this device, and also turn it in the opposite direction. In the Archimedes turbine, water flowing downward turns the screw, which itself is the center of a hydroelectric generator.

Within a few centuries of their invention, screws were appearing all around the Mediterranean in the form of wooden screw presses. We used these to smash olives for olive oil and to smash grapes for wine — both major products of the region. Later on, the screw press would also be a vital component of Gutenberg's printing press.

Me, rummaging for my turnscrew.

Have you noticed a pretty major use that's missing here?

That's right: screws weren't used as fasteners. Instead, there were nails, welding, dowels and pins, etcetera, etcetera. This list of “alternatives” is substantial. In fact, we didn’t use screws as fasteners for nearly two millennia after Archimedes invented them.

What was missing? The screwdriver. (Fun fact: we used to call screwdrivers “turnscrews.”) We didn’t invent the screwdriver until the 1500s. Even then, we rarely tended to use screws as fasteners.

The final piece of the puzzle? The creation of machine tools necessary for manufacturing metal screws. Until that happened, they were just too much trouble to produce in large quantities.

Since we optimized that production angle, we haven't stopped turning them out.


Archimedes' screw gif by Silberwolf (size changed by: Jahobr), CC BY-SA 2.5, via Wikimedia Commons.

The Yard Ramp Guy Blog: State Ramp Coverage

This week, my friend The Yard Ramp Guy explains how Alaska, aka The Last Frontier, is not that at all, so far as yard ramp coverage is concerned.

Click HERE to boldly go where no Yard Ramp Guy ramp has gone before.

Archives: Space Elevators

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original contributions. And so, my From the Archives series. This week: The ups and downs of space elevators.

When it comes to getting into space, rockets are pretty much staircases at best. More like ladders, really.

McCoy Fields: Going Up!

Space Elevator

That's a bizarre thing to say, I know, but hear me out. Rockets are expensive and dangerous, but they're still the best way we have of getting to space. (There are a couple of other ways, like Orion drives, but given that those things basically ride nuclear explosions...) There's a theoretical method, that works much, much better: the space elevator. (Hence the staircase joke. Well, I thought it was funny, at least. So I'm not a professional comedian, so sue me.)

A space elevator is, essentially, a long cable—anchored at the equator, extending out into orbit. It works sort of like when you spin while holding a rope, and the rope is suspended above the ground by centrifugal force. (Or is it centripetal? I can never remember.) It's not quite the same, of course, since it has to have a counterweight at the end, along with several other requirements.

Once the cable is up, cargo and passenger pods would be able to freely move up and down it, at much, much lower costs than rockets.

Did I mention how expensive rockets are? Really, really expensive. As in: $10,000 to $25,000 per kilogram they need to lift. (For those of you who don't have your measurement conversion tables memorized, one kilogram is equal to a bit more than two pounds.)

Carbon Tube

A Carbon Tube

So why aren't we using them now? Well, because we don't have a strong enough cable. People keep bringing up carbon nanotubes as an option, but since we don't have those yet, we just can't build it.

The space elevator would be more than possible on other, smaller objects in the Solar System. We could build a space elevator on the moon with ordinary Kevlar.

Space elevators aren't the only ideas for getting to space without rockets. Other ideas are floating out there, ranging from rocket sleds (which does actually involve rockets, but in a much more affordable manner) to skyhooks, which resemble something that a mad scientist, a six year old, and an engineer would design together if asked to create the nuttiest amusement park ride ever, all while hooked to caffeine IV drips.

The Yard Ramp Guy Blog: Steel Evolution

This week, my friend The Yard Ramp Guy impressively shows us how words matter in influencing hearts and minds.

Click HERE to read those words.

Archives: The Amazing Spider, Man

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original contributions. And so, my From the Archives series. This week: spider silk!

Oh, What a Tangled Web We Weave

Another Busy Day at the Office?

If you're not a fan of spiders, you may want to skip this one. Otherwise, I just might’ve already snared you:

Spider silk is one of the most magnificent substances in nature, and there are a ton of different types of spider silk.

The silk can be used to capture prey. Along with their classic web-shaped design, spiders build webs in orbs, tangles, sheets, lace, and domes. One type of spider even lowers single-strand webs to go fishing.

Spiders tie up their prey in webs; a few species actually have venomous webs they use for this purpose. Other spiders produce extremely lightweight webs for “ballooning”—spiders blown along for dozens or even hundreds of miles by the wind, often in enormous swarms. (Yay, Australia!) Others use silk to lay trails to and from their web, and create alarm lines with it.

On top of that, spiders usually are capable of creating multiple types of silk—up to seven types in a single species.

Humans have studied and adapted countless different uses for spider silk. The spider-silk protein is comparable in tensile strength to high-grade alloy steel at one-sixth the density. We have stronger materials, like Kevlar, but none nearly so lightweight. (The strongest spider silk variety is more than ten times stronger than Kevlar.)

Spider silk is extremely stretchy and ductile, retaining its useful properties across a huge temperature range. The silk even makes for excellent bandages, due to its antiseptic qualities, and contains high amounts of vitamin K, which is useful in clotting blood.

Yes, the stuff that spiders spin is extremely useful. So, why don't we use it industrially? Because spider-farming doesn't work. Spiders eat each other. Instead, we've turned to genetic engineering. We've tried altering silkworms, E. Coli, goats (they produced it in their milk), tobacco plants, and potato plants to produce the protein.

We haven't mastered silk well enough to mass-produce, yet, but it'll happen eventually. (And then we'll get spider-web suspension bridges. Completely not creepy!)

The Yard Ramp Guy Blog / A Yard Ramp Guy Primer

This week, my friend The Yard Ramp Guy describes how his company rents, sells, and buys new and used yard ramps throughout the United States. It's quite detailed and fascinating.

Click HERE to read the impressive scope of his operation.

From the Archives: Kitchen Marvels

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original contributions. And so: my From the Archives series. This week: the marvels of technology can readily be found in your very own kitchen.

The Modern Kitchen

The history of technology we usually teach kids is a flashy one. They hear about atomic bombs, rocket ships, computers. If it's big, shiny, immensely expensive and difficult to create, oh, and explodes, we teach them about it. Occasionally, we might mention a really important, yet more boring one, like nitrogen fertilizers. But generally? It's shiny objects all the way down.

Modern nitrogen fertilizers, are, in my book, the most important invention of the 20th century. Forget computers, forget atom bombs: nitrogen fertilizers are what allow us to maintain our global population levels—and they might get a few sentences in your average grade school history book.

When you look at even less-flashy inventions, they get less and less in the way of attention paid to them. In fact, I can almost guarantee that you never think about one of the categories of devices you use most often. Kitchenware.

Seriously. Go in your kitchen right now, and pick up…let's say, a rubber spatula. We've had rubber for much, much longer than we've had rubber spatulas, so why did we invent them? Well, you probably have a non-stick pan, right? Try scraping it out with a metal spatula, and you're going to scrape off the non-stick coating. (Which, apparently, is really bad for your health.)

Or take a look at cast iron pans. They've got a bit of a reputation for being a little on the tough side to clean, right? Well, they used to be considerably easier to clean, but as they drifted a bit more out of popular use (though never went completely absent), a final step of the production process was dropped. They used to be sand casted, then given a strong polish, but this polishing step was dropped to save on costs, so antique cast iron is actually considerably more non-stick.

Every single pot, pan, knife, item of silverware, or bizarre back-of-the-drawer gizmo in your kitchen has an extensive history all its own. And even a cultural context: five centuries ago, a muffin pan would have been pretty much useless scrap, thanks to the lack of common closed range stoves. These are tools that you use constantly and are personally relevant every day. Atom bombs? They can, really, only be personally relevant once.


Photo by Todd Ehlers from McGregor, Iowa, a Mississippi River town, U.S. of A. (1937 Kitchen--Not Bad!) [CC BY 2.0], via Wikimedia Commons.

The Yard Ramp Guy Blog: Ramping Toward 2021

My friend The Yard Ramp Guy puts a noble spin on the year that was, and he looks forward to putting it all behind us.

Click HERE to review the world with him.